Theodora Ross, M.D., Ph.D., helps people understand what their genes might be telling them about their risk for cancer.

Dr. Ross directs UT Southwestern Medical Center’s Cancer Genetics Program, which sees more than 2,000 patients every year. The physicians and genetic counselors in the Cancer Genetics Clinic help patients assess their risk for many types of cancer, including kidney, skin, lung, breast, ovarian, colon, endocrine and prostate cancers.

Twenty years ago, this type of work would have been impossible.

“Back then, this type of clinic didn’t exist; we didn’t know how to use the genetic information that we had,” says Dr. Ross. “Today we do. And we can save people’s lives. It’s such an exciting time.”

People who have a family history of cancer come to the Cancer Genetics Clinic to work with Dr. Ross and a genetic counselor. If a known genetic predisposition to cancer is found, Dr. Ross and her team counsel the patient about the best ways to prevent cancer from ever forming.

Patients who already have cancer also benefit from genetic testing, Dr. Ross says.

“Genetic testing can help us make important decisions about the best method of treatment. For breast cancer, for example, we can do a quick test to determine whether patients have a certain mutation, which could help decide whether they will have bilateral mastectomy versus just a lumpectomy.”

In addition, genetic testing can help physicians determine which chemotherapy to recommend, and whether an investigational drug might be warranted.

Dr. Ross is also a scientist, and she leads a laboratory that investigates how cells transform from normal cells to cancer cells, and how some cancer cells are able to withstand specifically targeted cancer drugs. One of her main areas of investigation is the BRCA1 gene, which – when abnormal – predisposes women to breast and ovarian cancer.

Dr. Ross says she’s passionate about combining fundamental scientific research with medicine because there is still so much to learn about how the genes we inherit affect the potential development of cancer.

“Whether or not a variant in any gene causes disease is the big question we still need to answer in many cases,” she says. “There are 25,000 genes in our genome, and our studies have shed light on only about 6,000 of them. And of those, we know only about 100 genes that cause cancer when they’re faulty.”

While that means there’s still a lot to learn about the human genome and cancer, Dr. Ross says it also means that another revolution in cancer genetics is just around the corner.